Borates

Read and learn about borates and the concepts related to them, along with their uses in this study material.

Boron is the fifth element on the periodic table. The minerals that naturally occur in nature containing this element are called borates. Boron cannot exist by itself in nature. It has to combine with other elements, either forming boric acid or inorganic salts, which are called borates. 

BO33−is the simplest ion of borate. These ions form salts with metallic elements. Ulexite, colemanite, and borax are some borate minerals that occur naturally. Borates have a number of applications in various aspects of life. 

Types of Naturally Occurring Borates

  1. Ulexite: The chemical formula of ulexite is NaCaB5O6(OH)6·5H2O, and it is read as hydrated sodium calcium borate hydroxide. They occur either as round crystals, which are white in colour or as fibrous crystals, which are closely packed. It has some unusual optical characteristics, due to which it is referred to as ‘TV rock’. 
  2. Colemanite: The chemical formula for colemanite is CaB3O4(OH)3·H2O. When borax and ulexite are altered, colemanite is formed. 
  3. Borax: Boron combines with oxygen and soda to form borax. Borax is the most commonly used borate. It exists in three forms – sodium borate formula, sodium tetraborate formula, and disodium tetraborate formula. Naturally occurring borax is first purified before it is used for any purpose. The purification is done by the process of recrystallization. The chemical formula of the most common type of borax is Na2B4O7·10H2O It is soft, colourless, and can dissolve in water. 

Types of Borates Formed in the Laboratory

  • B(OH)3 or B2O3 are made to react with metal oxides to form anhydrous compounds. The examples of such borates are as follows:
  • Metaborates containing the linear  [BO2]; it has three-coordinate boron.
  • Metaborates containing four coordinate boron
  • Triborate  B3O75-,, as in CaAlB3O7 (johachidolite)
  • Tetraborate B4O96− as in Li6B4O9
  • Diborate B2O54−, as in Mg2B2O5 (suanite)
  • In aqueous form, borates exist as near-neutral or acidic forms. An example of this form of borate is boric acid. Boric acid is a weak acid. It exists as a colourless crystal or white powder. Its molecular formula is H3BO3, and it has many antiviral, antifungal, and antiseptic properties. Boric acids are highly soluble in water. They are reacted with alcohol to form borate esters.

Physical Properties of Borates

The physical properties of borate are as follows:

  • It is soluble in water.
  • Borates are white in colour.
  • Its density is 1.73 g/dm3.

Chemical Properties of Borates

The chemical properties of borate are as follows: 

  • It is flammable.
  • Borates show reactivity towards ethylene glycol.
  • They are sparingly soluble in acetone.

Application of Borates

There are many applications of borates, some of which are as follows:

  1. Detergents: Borates are a crucial component in detergents. They have bleaching effects that aid in bleaching and stain removal. Borates are used in other cleaning products as well.
  2. pH stabiliser: Borates are used in many film processing solutions and fireworks to balance the acidity and alkalinity of it. 
  3. Dispersion: Borates are mixed with adhesives and paints as they have high bonding properties. This helps in the even dispersion of the particles of such materials.
  4. Rustproofing: Borates are a part of the composition of the coatings on iron. This prevents corrosion caused by rusting.
  5. Flame proofing: Borates are flame retardants. They are used in cellulose insulation. In polymers, they are used to suppress smoke and retard flames after combining them with zinc. 
  6. Ceramics: Borates enhance lustre in ceramics. They are used for enamelling and glazing ceramic wares.
  7. Agriculture: Boron is vital for agriculture. Seeding, fruiting, and fertilisation in plants are not possible without them. Borate fertilisers are used in agriculture to increase crop yields as it aids in the proper nourishment of plants.  

Are Borates Safe?

Borates are widely used everywhere for different purposes. Although they are toxic, the degree of toxicity is less. Borates are primarily used in agriculture, as it is still one of the safest compounds that can be used in fertilisers. A small amount of borate causes no hazard to human life. However, if ingested or inhaled in large quantities, it might cause irritation, nausea, vomiting, and diarrhoea. Some harmful effects of borates are listed as follows: 

  • Harms the male reproductive system
  • Leads to miscarriages in pregnant women
  • Disrupts the hormones in the body
  • Causes skin allergies
  • Irritates the eyes
  • Leads to the toxicity of organs

Conclusion

Borates are crucial compounds used everywhere. They are employing materials which consist of borates in our lives every day. Whether it is cleaning products or agricultural practices, borates have some major applications. One of the most important uses of borates comes from their property of being flame retardant. Its coating helps resist flame, which aids in fireproofing. 

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What are borates?

Ans. Boron is the fifth element on the periodic table. The minerals that naturally occur in nature containing this e...Read full

What is boric acid?

Ans. Boric acid is a weak acid. It exists as a colourless crystal or white powder. ...Read full

Why are borates used in laundry detergents?

Ans. Borates naturally have bleaching properties. Thus, they are used in laundry detergents, cleaning solutions, and...Read full

Are borates safe to use?

Ans. Borates are widely used everywhere for different purposes. Although borates are toxic, the degree of toxicity i...Read full